Asynchronous learning is a general term used to describe forms of education, instruction, and learning that do not occur in the same place or at the same time. It uses resources that facilitate information sharing outside the constraints of time and place among a network of people. In many instances, well-constructed asynchronous learning is based on constructivist theory, a student-centered approach that emphasizes the importance of peer-to-peer interactions. This approach combines self-study with asynchronous interactions to promote learning, and it can be used to facilitate learning in traditional on-campus education, distance education, and continuing education. This combined network of learners and the electronic network in which they communicate are referred to as an asynchronous learning network.

Online learning resources that can be used to support asynchronous learning include email, electronic mailing lists, threaded conferencing systems, online discussion boards, wikis, and blogs. Course management systems have been developed to support online interaction, allowing users to organize discussions, post and reply to messages, and upload and access multimedia. These asynchronous forms of communication are sometimes supplemented with synchronous components, including text and voice chat, telephone conversations, videoconferencing, and even meetings in virtual spaces such as Second Life, where discussions can be facilitated among groups of students.

The roots of asynchronous learning are in the end of the 19th century, when formalized correspondence education (or distance learning) first took advantage of the postal system to bring physically remote learners into the educational fold. The 1920s and 1930s saw the introduction of recorded audio, desynchronizing broadcasting and revolutionizing the mass dissemination of information. The first significant distribution of standardized educational content took place during World War II; the branches of the US military produced hundreds of training films, with screenings numbering in the millions.

Online asynchronous learning began with schools' and universities' substantial investment in computer technology in the early 1980s. With seminal applications such as Seymour Papert's Logo programming language, students were able to learn at their own pace, free from the synchronous constraints of a classroom lecture. As computers entered more households and schools began connecting to the nascent Internet, asynchronous learning networks began to take shape. These networks augmented existing classroom learning and led to a new correspondence model for solitary learners.

Using the web, students could access resources online and communicate asynchronously using email and discussion boards. The 1990s saw the arrival of the first telecampuses, with universities offering courses and entire degree plans through a combination of synchronous and asynchronous online instruction. Advancements in multimedia and interactivity have increased the effectiveness of asynchronous learning networks, reducing the distinction between content creators and consumers. Tools such as class blogs and wikis provide enhanced opportunities for asynchronous interaction and learning.

Though the social relationships integral to group learning can be developed through asynchronous communication, this development tends to take longer than in traditional, face-to-face settings. The establishment of an asynchronous community takes time and effort and tends to follow a projected course of five stages, as described by Waltonen-Moore et al.:

Asynchronous communities that progress efficiently through these stages tend to share at least three common attributes:

First, the community has an active facilitator who monitors, guides, and nurtures the discourse. Unguided communities tend to have difficulty progressing beyond the second stage of development, because group members can become distracted from the community's intended purpose.